Print quality, ink adhesion, rub resistance, or durability are factors that designers and users of printers consider. Such advantages are, generally, in particular desired by commercial printing customers. One manner to improve image durability is to provide a coating on a print medium. The coating may be provided over the printed image printed, which is referred to as an overcoat. Alternatively, the coating may be provided onto the surface of the print medium, which is referred to as an undercoat. An image may be then subsequently printed on the coated print medium.
An undercoat may be applied to enhance fixation (e.g., bonding and/or hardening) of a colorant to be subsequently applied on the print medium. If the colorant includes an ink, fixation may be desired to address coalescence, bleed, feathering, or similar effects characterized by ink or pigment migration across a printed surface. An overcoat may be applied as a protection to improve durability of the printed image.
Some methods for applying coatings on a substrate include roll coating, spray coating, manual application, or treatment ejection, for example, through a jetting device.